Yep, clowns were cultural pranksters long before they morphed into merry fools. They also bore less-than-sterling names such as “stupidus,” “scurra” and “moriones” (from which “stupid,” “scurrilous” and “moron” are derived).

So why should we be surprised that clowns are back to being creepy? Psychologists, sociologists and anthropologists aren’t.

A study released last year involving an international sample of more than 1,300 people put “clown” at the top of a list of creepiest occupations, ahead of taxidermist, sex shop owner and funeral director. (Oddly, “writer” came in 11th, just ahead of actor, construction worker and computer software engineer.)

The lead author of the study, psychologist Francis McAndrew, wrote in the journal article, “On the nature of creepiness,” that it was “things that make a person unpredictable also predict creepiness.” And clowns, frankly, fit the bill. They wear disguises, might appear to be friendly or happy from their face paint and yet behave differently, and you don’t know what they might do next.

“It may be that it is only when we are confronted with uncertainty about threat that we get ‘creeped out,’ ” McAndrew wrote, “which could be adaptive if it facilitates our ability to maintain vigilance during periods of uncertainty. Thus, it is our contention that ‘creepy’ is a qualitatively different characteristic than related concepts such as ‘terrifying’ or ‘disgusting’ in which the conclusions drawn about the person in question are much more clear cut.”